Question

the bird watcher counted the number of birds in each flock that passed overhead.
birds per flock
stem | leaf
2 | 2 5 9
3 | 3 4 7 7 8
4 | 8 9
5 | 1 3 4 8 8
6 | 2 4 5 5 6 7
how many flocks had at least 30 birds?
flocks
submit

Explanation:

Step1: Analyze stem 2

Stem 2 represents numbers in the 20s (20 - 29). Since we need at least 30, we exclude stem 2. The number of flocks in stem 2: 3 (leaves 2,5,9). But we don't count these.

Step2: Analyze stem 3

Stem 3 represents numbers in the 30s (30 - 39). The leaves are 3,4,7,7,8. So number of flocks: 5.

Step3: Analyze stem 4

Stem 4 represents numbers in the 40s (40 - 49). The leaves are 8,9. Number of flocks: 2.

Step4: Analyze stem 5

Stem 5 represents numbers in the 50s (50 - 59). The leaves are 1,3,4,8,8. Number of flocks: 5.

Step5: Analyze stem 6

Stem 6 represents numbers in the 60s (60 - 69). The leaves are 2,4,5,5,6,7. Number of flocks: 6.

Step6: Sum the counts

Now sum the number of flocks from stems 3,4,5,6: \(5 + 2 + 5 + 6 = 18\).

Answer:

18